U.S. patent application number 15/979076 was filed with the patent office on 2018-09-13 for image reading apparatus.
The applicant listed for this patent is CANON DENSHI KABUSHIKI KAISHA. Invention is credited to Yuji Gotoh, Hiroshi Komuro, Tatsuya Nishi, Yoshihiro Taniike.
Application Number | 20180262646 15/979076 |
Document ID | / |
Family ID | 58718022 |
Filed Date | 2018-09-13 |
United States Patent
Application |
20180262646 |
Kind Code |
A1 |
Gotoh; Yuji ; et
al. |
September 13, 2018 |
IMAGE READING APPARATUS
Abstract
There is provided an image reading apparatus including a first
reading sensor provided in a first reading unit and configured to
read one surface of the sheet, a second reading sensor provided in
a second reading unit provided to face the first reading sensor and
configured to read an image on the other surface of the sheet, a
first background portion serving as a reading background of the
first reading sensor, a second background portion serving as a
reading background of the second reading sensor, and a moving
portion configured to integrally move the first reading sensor and
the second background portion, wherein the first reading unit
includes a sensor case in which the first reading sensor is
provided, and the sensor case is fixed to the apparatus main
body.
Inventors: |
Gotoh; Yuji; (Kawaguchi-shi,
JP) ; Komuro; Hiroshi; (Wako-shi, JP) ; Nishi;
Tatsuya; (Funabashi-shi, JP) ; Taniike;
Yoshihiro; (Tokyo, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
CANON DENSHI KABUSHIKI KAISHA |
Chichibu-shi |
|
JP |
|
|
Family ID: |
58718022 |
Appl. No.: |
15/979076 |
Filed: |
May 14, 2018 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
PCT/JP2016/084284 |
Nov 18, 2016 |
|
|
|
15979076 |
|
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04N 1/028 20130101;
H04N 1/2032 20130101; H04N 2201/044 20130101; G06T 1/00 20130101;
H04N 1/00 20130101; G03G 15/00 20130101; H04N 1/04 20130101; H04N
1/00742 20130101; H04N 1/4095 20130101; G03B 27/62 20130101 |
International
Class: |
H04N 1/409 20060101
H04N001/409; H04N 1/00 20060101 H04N001/00 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 20, 2015 |
JP |
2015-228151 |
Nov 20, 2015 |
JP |
2015-228152 |
Nov 20, 2015 |
JP |
2015-228153 |
Nov 20, 2015 |
JP |
2015-228154 |
Claims
1. An image reading apparatus comprising: an apparatus main body
including a feeding unit for feeding a sheet; a first reading
sensor provided in a first reading unit and configured to read one
surface of the sheet moving along a conveyance path; a second
reading sensor provided in a second reading unit provided to face
the first reading sensor via the conveyance path and configured to
read an image on the other surface of the sheet; a first background
portion provided at a readable position of the first reading sensor
and serving as a reading background of the first reading sensor; a
second background portion provided at a readable position of the
second reading sensor and serving as a reading background of the
second reading sensor; and a moving portion configured to
integrally move the first reading sensor and the second background
portion along the conveyance path, wherein the first reading unit
includes a sensor case in which the first reading sensor is
provided, and the sensor case is fixed to the apparatus main body,
and wherein the first reading unit is able to move between a
position where the first reading unit faces to the first background
portion and receives reflection light from the first background
portion and a positon where a black background portion which does
not have surface reflecting light to the first reading unit is
placed.
2. The image reading apparatus according to claim 1, further
comprising a third background portion which is opposite to the
second reading sensor and is arranged parallel to the first
background portion in the conveyance path, wherein the third
background portion has a inclined surface arranged between the
third background portion and the first background portion, and
wherein a position of the black background is a position where the
first reading unit faces to the inclined surface.
3. The image reading apparatus according to claim 1, wherein the
reading backgrounds of the first reading sensor and the second
reading sensor can be switched simultaneously by causing the moving
portion to integrally move the first reading sensor and the second
background portion along the conveyance path.
4. The image reading apparatus according to claim 1, further
comprising a fourth background portion which is opposite to the
second reading sensor is arranged parallel to the second background
portion in the conveyance path.
5. The image reading apparatus according to claim 4, wherein the
second reading sensor, the first background portion, and the third
background portion are arranged adjacent to each other in that
order, and the first reading sensor, the second background portion,
and the fourth background portion are arranged adjacent to each
other in that order.
6. The image reading apparatus according to claim 4, wherein
background colors of the first background portion and the second
background portion are white, and the third background portion and
the fourth background portion are black.
7. The image reading apparatus according to claim 1, wherein the
second reading sensor is movable in a direction perpendicular to a
conveyance direction.
8. The image reading apparatus according to claim 2, wherein the
third background portion is a wall surface of a fixing member to
which the first background portion is attached.
9. The image reading apparatus according to claim 2, wherein the
inclined surface forms an obtuse angle with a normal to the
conveyance path.
10. The image reading apparatus according to claim 2, wherein a
wall surface, facing the third background portion in parallel to
the conveyance path, of the first reading unit is a dark color
surface.
11. The image reading apparatus according to claim 1, wherein the
first reading unit and the second reading unit have structures
arranged to have point symmetry with respect to the conveyance
path.
12. The image reading apparatus according to claim 1, further
comprising: a second unit to which a first unit including an
electric component is pivotably attached; a sheet conveyance path
formed between the first unit and the second unit in a closed state
in which the first unit is closed with respect to the second unit;
and an elastic member configured to press the first unit in an
opening direction from the closed state, wherein the elastic member
is a conductive member, and in the closed state, one end of the
elastic member contacts a conducting portion of the first unit and
the other end of the elastic member contacts a conducting portion
of the second unit.
13. The image reading apparatus according to claim 1, further
comprising: a reading unit configured to read an original conveyed
along a conveyance path; an opening/closing unit configured to be
opened/closed to open the conveyance path; a fixing unit, arranged
along the conveyance path, for fixing the reading unit; and a
reading unit releasing biasing unit for biasing the fixed reading
unit toward a side of the conveyance path, wherein the fixing unit
can be released from the side of the conveyance path, and if fixing
of the reading unit by the fixing unit is released, the reading
unit is pushed out of the storage portion to the side of the
conveyance path by the reading unit releasing biasing unit.
14. The image reading apparatus according to claim 1, further
comprising: an apparatus main body including a conveyance unit for
conveying an original; a sensor case mounted along a conveyance
path of the apparatus main body; a reading sensor provided to be
movable in a conveyance direction of the original in the sensor
case and configured to read one surface of the original; a
background member provided to face the reading sensor via the
conveyance path and including a first background portion and a
second background portion arranged side by side in the conveyance
direction of the original; and a sensor moving member configured to
move the reading sensor in the conveyance direction of the
original, wherein the sensor moving member is engaged with the
reading sensor by being attached to the sensor case from an
opposite side of the conveyance path, and includes a driving source
configured to transfer a driving force from an opposite side of the
side of the reading sensor to the sensor moving member.
Description
[0001] This application is a continuation of International Patent
Application No. PCT/JP2016/084284 filed on Nov. 18, 2016, and
claims priority to Japanese Patent Application Nos. 2015-228153,
2015-228151, 2015-228152, and 2015-228154, filed Nov. 20, 2015, the
entire contents of which are incorporated herein by reference.
TECHNICAL FIELD
[0002] The present invention relates to an image reading apparatus
for reading an original while conveying the original.
BACKGROUND ART
[0003] There is conventionally provided an image reading apparatus
that causes two image reading units to read images on the obverse
and reverse surfaces of an original and is mounted with both white
and black background members. To suppress show-through when an
original is a thin paper sheet, the black surface is arranged
behind the original. To suppress reading of a portion around an
original in black when the original is of an irregular size, the
white surface is arranged behind the original.
[0004] To switch the background color, a movable mechanism is
required. In an image reading apparatus described in PTL 1, there
is proposed a method of switching the background color by causing
the movable mechanism to move one of reading units for the obverse
and reverse surfaces in a conveyance direction to change the
position of an image reading portion. In this arrangement, when the
reading unit moves, a white background plate or a black background
plate is arranged to face the reading positions of the image
reading units for both the obverse and reverse surfaces.
CITATION LIST
Patent Literature
[0005] PTL 1: Japanese Patent Laid-Open No. 2001-16412
SUMMARY OF INVENTION
Technical Problem
[0006] However, if the technique described in PTL 1 is applied to
background switching of the image reading apparatus including the
two image reading units, it is necessary to ensure a space to move
a housing including an optical system for reading each of the white
background plate and the black background plate, thereby increasing
the size of the overall apparatus.
Solution to Problem
[0007] According to the present invention, for example, there is
provided an image reading apparatus comprising: an apparatus main
body including a feeding unit for feeding a sheet; a first reading
sensor provided in a first reading unit and configured to read one
surface of the sheet moving along a conveyance path; a second
reading sensor provided in a second reading unit provided to face
the first reading sensor via the conveyance path and configured to
read an image on the other surface of the sheet; a first background
portion provided at a readable position of the first reading sensor
and serving as a reading background of the first reading sensor; a
second background portion provided at a readable position of the
second reading sensor and serving as a reading background of the
second reading sensor; and a moving portion configured to
integrally move the first reading sensor and the second background
portion along the conveyance path, wherein the first reading unit
includes a sensor case in which the first reading sensor is
provided, and the sensor case is fixed to the apparatus main body,
and wherein the first reading unit is able to move between a
position where the first reading unit faces to the first background
portion and receives reflection light from the first background
portion and a positon where a black background portion which does
not have surface reflecting light to the first reading unit is
placed.
Advantageous Effects of Invention
[0008] According to the present invention, it is possible to
provide a technique of downsizing an apparatus by enabling
background switching with a structure in which a reading unit is
fixed to the main body of an image reading apparatus.
[0009] Other features and advantages of the present invention will
be apparent from the following description taken in conjunction
with the accompanying drawings. Note that the same reference
numerals denote the same or like components throughout the
accompanying drawings.
BRIEF DESCRIPTION OF DRAWINGS
[0010] The accompanying drawings, which are incorporated in and
constitute a part of the specification, illustrate embodiments of
the invention and, together with the description, serve to explain
the principles of the invention.
[0011] FIG. 1 is a schematic view showing an image reading
apparatus according to the first embodiment of the present
invention;
[0012] FIG. 2 is a block diagram showing a control unit of the
image reading apparatus shown in FIG. 1;
[0013] FIG. 3 is a front view showing the image reading apparatus
according to the first embodiment of the present invention;
[0014] FIG. 4 is another front view showing the image reading
apparatus according to the first embodiment of the present
invention;
[0015] FIG. 5 is a plan view showing the image reading apparatus
according to the first embodiment of the present invention;
[0016] FIG. 6 is another plan view showing the image reading
apparatus according to the first embodiment of the present
invention;
[0017] FIG. 7 is a schematic sectional view showing the image
reading apparatus according to the first embodiment of the present
invention;
[0018] FIG. 8 is another schematic sectional view showing the image
reading apparatus according to the first embodiment of the present
invention;
[0019] FIG. 9 is a side view showing the image reading apparatus
according to the first embodiment of the present invention;
[0020] FIG. 10 is a side view showing the image reading apparatus
according to the first embodiment of the present invention;
[0021] FIG. 11 is a schematic sectional view showing the image
reading apparatus according to the first embodiment of the present
invention;
[0022] FIG. 12A is a schematic sectional view showing the image
reading apparatus according to the first embodiment of the present
invention;
[0023] FIG. 12B is a schematic sectional view showing the image
reading apparatus according to the first embodiment of the present
invention;
[0024] FIG. 13 is a perspective view showing a CIS;
[0025] FIG. 14A is a sectional view showing a reading unit 70;
[0026] FIG. 14B is a sectional view showing the reading unit
70;
[0027] FIG. 15 is an enlarged view showing a portion near a feeding
unit of an image reading apparatus according to the second
embodiment of the present invention;
[0028] FIG. 16 is a schematic view showing a lock portion according
to the second embodiment of the present invention;
[0029] FIG. 17 is a front view showing an upper unit when viewed
from a side of a conveyance path RT of the image reading apparatus
according to the second embodiment of the present invention;
[0030] FIG. 18 is an enlarged view showing the main part of the
image reading apparatus according to the second embodiment of the
present invention;
[0031] FIG. 19 is a front view showing the lower unit when viewed
from the side of the conveyance path RT of the image reading
apparatus according to the second embodiment of the present
invention;
[0032] FIG. 20 is a sectional view showing the electrical
connection state of the image reading apparatus according to the
second embodiment of the present invention;
[0033] FIG. 21 is a sectional view showing the electrical
connection state of an image reading apparatus according to the
third embodiment of the present invention;
[0034] FIG. 22 is a perspective view showing an image reading
apparatus according to the fourth embodiment of the present
invention;
[0035] FIG. 23A is an enlarged view showing the main part of the
image reading apparatus according to the fourth embodiment of the
present invention;
[0036] FIG. 23B is an enlarged view showing the main part of the
image reading apparatus according to the fourth embodiment of the
present invention;
[0037] FIG. 24A is a schematic partial sectional view showing the
image reading apparatus according to the fourth embodiment of the
present invention;
[0038] FIG. 24B is a schematic partial sectional view showing the
image reading apparatus according to the fourth embodiment of the
present invention;
[0039] FIG. 25A is a perspective view showing an image reading
apparatus according to the fifth embodiment of the present
invention;
[0040] FIG. 25B is a perspective view showing the image reading
apparatus according to the fifth embodiment of the present
invention;
[0041] FIG. 26A is a schematic sectional view showing an image
reading lower unit of the image reading apparatus according to the
fifth embodiment of the present invention;
[0042] FIG. 26B is a schematic sectional view showing the image
reading lower unit of the image reading apparatus according to the
fifth embodiment of the present invention;
[0043] FIG. 27A is a schematic sectional view showing image reading
units of the image reading apparatus according to the fifth
embodiment of the present invention;
[0044] FIG. 27B is a schematic sectional view showing the image
reading units of the image reading apparatus according to the fifth
embodiment of the present invention;
[0045] FIG. 28A is another schematic sectional view showing the
image reading lower unit of the image reading apparatus according
to the fifth embodiment of the present invention;
[0046] FIG. 28B is still another schematic sectional view showing
the image reading lower unit of the image reading apparatus
according to the fifth embodiment of the present invention;
[0047] FIG. 29A is still another schematic sectional view showing
the image reading lower unit of the image reading apparatus
according to the fifth embodiment of the present invention;
[0048] FIG. 29B is still another schematic sectional view showing
the image reading lower unit of the image reading apparatus
according to the fifth embodiment of the present invention;
[0049] FIG. 30 is a perspective view showing a portion around a
position detection sensor in a state in which the image reading
lower unit of the image reading apparatus is detached according to
the fifth embodiment of the present invention;
[0050] FIG. 31 is schematic sectional view showing the portion
around the position detection sensor of the image reading apparatus
according to the fifth embodiment of the present invention;
[0051] FIG. 32 is a perspective view showing a CIS driving unit of
the image reading apparatus according to the fifth embodiment of
the present invention;
[0052] FIG. 33 is a schematic sectional view showing the CIS
driving unit of the image reading apparatus according to the fifth
embodiment of the present invention;
[0053] FIG. 34 is a schematic sectional view showing a portion
around a CIS sliding motor of the image reading apparatus according
to the fifth embodiment of the present invention; and
[0054] FIG. 35 is a schematic view showing a conventional
background switching mechanism.
DESCRIPTION OF EMBODIMENTS
First Embodiment
[0055] FIG. 1 is a schematic view showing an image reading
apparatus A according to the first embodiment of the present
invention.
[0056] <Arrangement of Apparatus>
[0057] The image reading apparatus A is an apparatus that conveys
one or a plurality of conveyance media S stacked on a mounting
table 1 into the apparatus through a route RT one by one, reads an
image of the medium, and discharges the medium to a discharge tray
2. The read conveyance medium S may be, for example, a sheet such
as an OA sheet, check, business card, or card, and may be a thick
or thin sheet. Examples of cards are a health insurance card,
license, and credit card. The conveyance medium S includes a book
such as a passport. When a book is a target, a holder can be used.
When a book in a double-page spread state is stored in the holder
and placed on the mounting table 1, the book is conveyed together
with the holder, and an image of the book can be read.
[0058] <Feeding>
[0059] A first conveyance unit 10 serving as a feeding mechanism
that feeds the conveyance medium S along the route RT is provided.
In this embodiment, the first conveyance unit 10 includes a feed
roller 11 and a separation roller 12 facing the feed roller 11, and
sequentially conveys the conveyance media S on the mounting table 1
in a conveyance direction D1 one by one. A driving unit 3 such as a
motor transfers a driving force to the feed roller 11 via a
transfer unit 5, and the feed roller 11 is rotationally driven in
the direction of an arrow in FIG. 1 (in a positive direction in
which the conveyance medium S is conveyed along the route RT). The
transfer unit 5 is, for example, an electromagnetic clutch, and
interrupts the driving force transferred from the driving unit 3 to
the feed roller 11.
[0060] <Driving Unit>
[0061] In this embodiment, the transfer unit 5 that connects the
driving unit 3 and the feed roller 11 is normally set in a state in
which the driving force is transferred, and interrupts the driving
force when the conveyance medium S is conveyed in a backward
direction. If the transfer unit 5 interrupts the transfer of the
driving force, the feed roller 11 is set in a freely rotatable
state. Note that the transfer unit 5 need not be provided if the
feed roller 11 is driven only in one direction.
[0062] <Separation Structure>
[0063] The separation roller 12 facing the feed roller 11 is a
roller for separating the conveyance media S one by one, and is in
press contact with the feed roller 11 with a constant pressure. To
ensure this press contact state, the separation roller 12 is
swingably provided and is configured to be biased against the feed
roller 11. The driving unit 3 transfers a driving force to the
separation roller 12 via a torque limiter 12a, and the separation
roller 12 is rotationally driven in the direction of a solid-line
arrow (in a direction opposite to the positive direction of the
feed roller 11).
[0064] Since the transfer of the driving force to the separation
roller 12 is regulated by the torque limiter 12a, when the
separation roller 12 abuts against the feed roller 11, the
separation roller 12 rotates together with the feed roller 11 (in
the direction of a broken-line arrow). With this operation, if the
plurality of conveyance media S are conveyed to a press-contact
portion between the feed roller 11 and the separation roller 12,
two or more conveyance media S except one conveyance medium S are
dammed not to be conveyed.
[0065] Note that the separation mechanism is formed by the
separation roller 12 and the feed roller 11 in this embodiment.
However, such separation mechanism need not always be provided. Any
feeding mechanism that sequentially feeds the conveyance media S to
the route RT one by one can be used. If the separation mechanism is
provided, a separation pad that applies a friction force to the
conveyance media S may be brought into press contact with the feed
roller 11 to perform the same separation operation, instead of the
component such as the separation roller 12.
[0066] <Conveyance Structure>
[0067] A second conveyance unit 20 serving as a conveyance
mechanism on the downstream side of the first conveyance unit 10 in
the conveyance direction includes a driving roller 21 and a driven
roller 22 driven by the driving roller 21, and conveys, to the
downstream side, the conveyance medium S conveyed from the first
conveyance unit 10. A driving unit 4 such as a motor transfers a
driving force to the driving roller 21, and the driving roller 21
is rotationally driven in the direction of an arrow in FIG. 1. The
driven roller 22 is in press contact with the driving roller 21
with a constant pressure, and rotates together with the driving
roller 21. The driven roller 22 may be configured to be biased
against the driving roller 21 by a biasing unit (not shown) such as
a spring.
[0068] A third conveyance unit 30 on the downstream side of the
second conveyance unit 20 in the conveyance direction includes a
driving roller 31 and a driven roller 32 driven by the driving
roller 31, and conveys the conveyance medium S conveyed from the
second conveyance unit 20 to the discharge tray 2. That is, the
third conveyance unit 30 functions as a discharge mechanism. The
driving unit 4 such as a motor transfers the driving force to the
driving roller 31, and the driving roller 31 is rotationally driven
in the direction of an arrow in FIG. 1. The driven roller 32 is in
press contact with the driving roller 31 with a constant pressure,
and rotates together with the driving roller 31. The driven roller
32 may be configured to be biased against the driving roller 31 by
a biasing unit (not shown) such as a spring.
[0069] The discharge tray 2 is axially supported via a first hinge
101 provided in a lower portion of the image reading apparatus A so
as to be pivotable with respect to the image reading apparatus A.
The discharge tray 2 is formed from a first discharge tray 2a on
the side of the first hinge 101 and a second discharge tray 2b
connected to the distal end of the first discharge tray 2a. The
second discharge tray 2b is axially supported to be pivotable with
respect to the first discharge tray 2a.
[0070] <Image Reading Structure, Control>
[0071] In the image reading apparatus A according to this
embodiment, an image reading unit 70 or 71 arranged between the
second conveyance unit 20 and the third conveyance unit 30 reads an
image, and thus the second conveyance unit 20 and the third
conveyance unit 30 convey the conveyance medium S at a constant
speed. By always setting a conveyance speed to a speed equal to or
higher than the conveyance speed of the first conveyance unit 10,
it is possible to reliably avoid a situation in which the
succeeding conveyance medium S catches up with the preceding
conveyance medium S. For example, in this embodiment, speed control
is performed so that the conveyance speed of the conveyance medium
S by the second conveyance unit 20 and the third conveyance unit 30
is higher than that by the first conveyance unit 10.
[0072] Note that even if the conveyance speed of the conveyance
medium S by the second conveyance unit 20 and the third conveyance
unit 30 is set to be equal to that by the first conveyance unit 10,
it is possible to form a minimum interval between the preceding
conveyance medium S and the succeeding conveyance medium S by
controlling the driving unit 3 to intermittently shift the feed
start timing of the succeeding conveyance medium S.
[0073] <Double Feed Detection>
[0074] A double feed detection sensor 40 arranged between the first
conveyance unit 10 and the second conveyance unit 20 is an example
of a detection sensor (a sensor for detecting the behavior or state
of a sheet) for detecting a state in which the conveyance media S
such as sheets pass through the first conveyance unit 10 while
being in tight contact with each other due to static electricity or
the like (that is, a double feed state in which sheets overlapping
each other are conveyed). Various kinds of sensors can be used as
the double feed detection sensor 40. In this embodiment, an
ultrasonic sensor is used, which includes an ultrasonic
transmission unit 41 and an ultrasonic reception unit 42, and
detects double feed on the principle that the attenuation amount of
an ultrasonic wave passing through the conveyance medium S when the
conveyance media S such as paper sheets are conveyed one by one is
different from that of an ultrasonic wave passing through the
conveyance media S when the conveyance media S are double-fed.
[0075] <Registration Sensor>
[0076] A medium detection sensor 50 arranged on the downstream side
of the double feed detection sensor 40 in the conveyance direction
is an example of an upstream-side detection sensor (a sensor for
detecting the behavior or state of a sheet) arranged on the
upstream side of the second conveyance unit 20 and on the
downstream side of the first conveyance unit 10, and detects the
position of the conveyance medium S conveyed by the first
conveyance unit 10, more specifically, whether the end portion of
the conveyance medium S has reached or passed through the detection
position of the medium detection sensor 50. Various kinds of
sensors can be used as the medium detection sensor 50. In this
embodiment, an optical sensor is used, which includes a light
emitting unit 51 and a light receiving unit 52 and detects the
conveyance medium S on the principle that a light reception
intensity (light receiving amount) changes when the conveyance
medium S reaches or passes through.
[0077] In this embodiment, the medium detection sensor 50 is
provided near the double feed detection sensor 40 on the downstream
side of it so that when the medium detection sensor 50 detects the
leading edge of the conveyance medium S, the conveyance medium S
reaches a position at which the double feed detection sensor 40 can
detect double feed. Note that the medium detection sensor 50 is not
limited to the above-described optical sensor. For example, a
sensor (image sensor or the like) capable of detecting the end
portion of the conveyance medium S or a lever type sensor
protruding to the route RT may be used.
[0078] A medium detection sensor 60 different from the medium
detection sensor 50 is arranged on the upstream side of the image
reading units 70 and 71. The medium detection sensor 60 is an
example of a downstream-side detection sensor arranged on the
downstream side of the second conveyance unit 20, and detects the
position of the conveyance medium S conveyed by the second
conveyance unit 20. Various kinds of sensors can be used as the
medium detection sensor 60. In this embodiment, an optical sensor
is used, similarly to the medium detection sensor 50, which
includes a light emitting unit 61 and a light receiving unit 62 and
detects the conveyance medium S on the principle that a light
reception intensity (light receiving amount) changes when the
conveyance medium S reaches or passes through. Note that in this
embodiment, the medium detection sensors 50 and 60 are respectively
arranged on the upstream and downstream sides of the second
conveyance unit 20 in the conveyance direction. However, only one
of the medium detection sensors 50 and 60 may be arranged.
[0079] <Arrangement of CIS>
[0080] Each of the image reading units 70 and 71 on the downstream
side of the medium detection sensor 60 is, for example, a unit for
optically scanning, performing conversion into an electrical
signal, and reading the signal as image data, and includes a light
source such as an LED, an image sensor, and a lens array.
[0081] <Explanation of Block Diagram>
[0082] A control unit 80 will be described with reference to FIG.
2. FIG. 2 is a block diagram showing the control unit 80 of the
image reading apparatus A.
[0083] The control unit 80 includes a CPU 81, a storage unit 82, an
operation unit 83, a communication unit 84, and an interface unit
85. The CPU 81 controls the overall image reading apparatus A by
executing a program stored in the storage unit 82. The storage unit
82 is formed from, for example, a RAM or a ROM. The operation unit
83 is formed by, for example, a switch or a touch panel, and
accepts an operation from an operator.
[0084] The communication unit 84 serves as an interface that
communicates information with an external apparatus. Assuming a PC
(Personal Computer) as an external apparatus, examples of the
communication unit 84 are a USB interface and a SCSI interface.
Instead of such a wired communication interface, a wireless
communication interface may be used as the communication unit 84,
or both a wired communication interface and a wireless
communication interface may be provided.
[0085] The interface unit 85 is an I/O interface that
inputs/outputs data to/from an actuator 86 and a sensor 87. The
actuator 86 includes the driving units 3 and 4 and the transfer
unit 5. The sensor 87 includes the double feed detection sensor 40,
the medium detection sensors 50 and 60, and the image reading units
70 and 71.
[0086] <Driving by Receiving Start Instruction from PC>
[0087] The basic operation of the image reading apparatus A will be
described. Upon receiving an image reading start instruction from,
for example, an external PC connected to the image reading
apparatus A, the control unit 80 starts to drive the first
conveyance unit 10 to the third conveyance unit 30. The conveyance
media S placed on the mounting table 1 are conveyed one by one from
the conveyance medium S at the lowest position. Alternatively, the
start time provided in the image reading apparatus A is accepted to
start a reading operation.
[0088] <Control at Time of Double Feed>
[0089] During conveyance of the conveyance medium S, the double
feed detection sensor 40 determines the presence/absence of double
feed. If the absence of double feed is determined, conveyance is
continued; otherwise, conveyance is stopped or feed of the
succeeding conveyance medium S by the first conveyance unit 10 is
stopped to discharge the conveyance media S in a double feed
state.
[0090] <Start of Reading Based on Output from Registration
Sensor>
[0091] At a timing based on the detection result of the medium
detection sensor 60, the control unit 80 starts to cause the image
reading unit 70 or 71 to read an image of the conveyance medium S
conveyed by the second conveyance unit 20, primarily stores the
read image, and transmits it to the external PC. The conveyance
medium S whose image has been read is discharged by the third
conveyance unit 30 to the discharge tray 2, thereby ending the
image reading processing of the conveyance medium S.
[0092] <Discharge Structure>
[0093] FIG. 3 is a front view showing a state in which the
discharge tray 2 of the image reading apparatus A is opened
according to the first embodiment of the present invention.
[0094] A display screen 93 is provided on a display panel 90 in an
upper front portion, and an operation key 122 is provided at an
adjacent position.
[0095] A discharge opening 92 is provided on a lower panel 91 in a
lower front portion, to which the conveyance medium S conveyed by
the third conveyance unit 30 is discharged.
[0096] FIG. 4 is a front view showing a state in which the
discharge tray 2 of the image reading apparatus A is stored
according to the first embodiment of the present invention.
[0097] The discharge tray 2 is axially supported via the first
hinge 101 provided in the lower portion of the image reading
apparatus A so as to be pivotable with respect to the image reading
apparatus A, and is configured to cover the front surface of the
main body with the first discharge tray 2a and the second discharge
tray 2b.
[0098] The first discharge tray 2a is attached to a main body 100
of the image reading apparatus A to be pivotable about the first
hinge 101. The first discharge tray 2a is formed in the same size
as an area obtained by combining the lower panel 91 and the
discharge opening 92, pivots about the first hinge 101 in the
stored state of the discharge tray 2 shown in FIG. 4, and is folded
to cover the lower panel 91 and the discharge opening 92.
[0099] The second discharge tray 2b is formed in the same size as
that of the display panel 90, pivots about a second hinge 102
provided at the distal end of the first discharge tray 2a in the
stored state of the discharge tray 2 shown in FIG. 4, and is folded
to overlap the display panel 90.
[0100] FIG. 5 is a plan view showing a state in which the discharge
tray 2 of the image reading apparatus A is opened according to the
first embodiment of the present invention.
[0101] The conveyance medium S conveyed by the third conveyance
unit 30 is discharged to the first discharge tray 2a via the
discharge opening 92, and reaches and is guided to the second
discharge tray 2b depending on the size of the conveyance medium
S.
[0102] The first discharge tray 2a is provided with a discharge
position adjustment member 120 to be pivotable. When, for example,
the conveyance medium S of a small size, such as a business card,
is discharged to the first discharge tray 2a, the discharge
position adjustment member 120 is made to pivot to an upright state
to adjust a position at which the conveyance medium S stops,
thereby making it possible to prevent the discharged conveyance
media S from being scattered.
[0103] In addition, the second discharge tray 2b is provided with a
translucent portion 121 that is arranged at a position overlapping
the operation key 122 provided in the display panel. The operation
key 122 is a power button that turns on/off the power of the main
body, and is configured to be turned on in a power-on state. With
the translucent portion 121 arranged at the position overlapping
the operation key 122, it is possible to confirm whether the
operation key 122 is in an ON state or an OFF state even in the
stored state of the discharge tray 2, thereby confirming the power
supply state of the image reading apparatus A.
[0104] <Arrangement of Display Panel>
[0105] In the stored state of the second discharge tray 2b, the
display screen 93 is arranged on the display panel 90 provided at a
position overlapping the second discharge tray 2b.
[0106] The display screen 93 is arranged to have a center line X at
the same position as that of the center line of a feeding tray 110
and a conveyance path width W. Note that a maximum conveyance path
width Wmax of the image reading apparatus A according to the first
embodiment of the present invention is set so as to feed a sheet of
a A4 letter size, and is Wmax=216 mm. The width of the display
screen 93 is 224 mm that exceeds Wmax.
[0107] This makes it possible to display, for example, a read image
in actual size on the display screen 93, and a finishing state can
be readily confirmed, thereby improving the user convenience.
[0108] <Details of Feed Structure>
[0109] FIG. 6 is a plan view showing the state in which the
discharge tray 2 of the image reading apparatus A is stored
according to the first embodiment of the present invention.
[0110] A regulating member 111 attached to be slidable in a
direction perpendicular to the conveyance direction in accordance
with the size of the arranged conveyance medium S is provided in
the mounting table 1.
[0111] <Details of Upper Unit>
[0112] FIG. 7 is a schematic sectional view showing the image
reading apparatus A according to the first embodiment of the
present invention.
[0113] The main body 100 is formed from an upper unit 103 and a
lower unit 104, and the upper unit 103 is attached to be pivotable
about a main body hinge 105 with respect to the lower unit 104.
[0114] Since the upper unit 103 includes, in the display panel 90,
the display screen 93 having a width exceeding the maximum
conveyance path width Wmax and the support frame metal plate of the
display screen 93, the barycenter in a state in which the upper
unit 103 is opened, as shown in FIG. 8, largely shifts toward the
front side in the conveyance direction with respect to the stored
state of the upper unit 103 shown in FIG. 1.
[0115] Therefore, the image reading apparatus A may fall if the
upper unit is opened quickly. However, by providing a protruding
portion 130 in the image reading apparatus A according to this
embodiment, it is possible to prevent the image reading apparatus A
from falling even if the barycenter moves along with opening of the
upper unit 103. The protrusion amount of the protruding portion 130
is a protrusion amount that is accommodated under the discharge
tray 2 in the stored state of the upper unit 103 and the discharge
tray 2 shown in FIG. 7, and extends to the front side in the
conveyance direction with respect to the barycenter of the upper
unit 103 in the open state of the upper unit 103 shown in FIG. 8.
This can prevent the image reading apparatus A from falling due to
opening of the upper unit 103, and prevent the protruding portion
from protruding more than necessary, in the stored state in which
the discharge tray 2 is stored, not to impede the user.
[0116] <Discharge Tray Angle Adjustment>
[0117] A tray support portion 131 that abuts against the lower
surface of the discharge tray 2 when the discharge tray 2 is opened
is pivotably provided on the upper surface of the protruding
portion 130.
[0118] As shown in FIG. 9, in the open state, the discharge tray 2
is supported by the protruding portion 130 so as to receive the
discharged conveyance medium S. As shown in FIG. 10, if the tray
support portion 131 is made to pivot to protrude upward from the
upper surface of the protruding portion 130, the tray support
portion 131 abuts against the lower surface of the discharge tray 2
to support the discharge tray 2, thereby making it possible to
adjust the angle of the discharge tray 2 from the state shown in
FIG. 9 in which the discharge tray 2 is supported by the protruding
portion 130.
[0119] For example, in the state shown in FIG. 10, the discharge
tray 2 is lifted up in the vertical direction, as compared with the
state shown in FIG. 9, thereby making it possible to change a
position where the leading edge of the conveyance medium S lands on
the upper surface of the discharge tray 2. Thus, in the state shown
in FIG. 9, if the leading edge of the conveyance medium S to be
discharged abuts against the trailing edge of the already
discharged conveyance medium S to push it, it is possible to make
the leading edge of the succeeding conveyance medium S reliably
land on the upper surface of the already discharged conveyance
medium S in addition to the effect of shifting the trailing edge of
the already discharged conveyance medium S toward the lower unit
104 by changing the angle of the discharge tray 2, as shown in FIG.
10. With this arrangement, it is possible to significantly improve
the aligning property of the discharged conveyance media S on the
discharge tray 2.
[0120] Note that the tray support portion 131 may be configured to
support the discharge tray 2 even in the middle of the pivoting
range, thereby adjusting the angle of the discharge tray 2 in a
plurality of stages. In this case, each conveyance medium S can be
received at an angle at which the aligning property on the
discharge tray 2 is highest, thereby improving the usability.
[0121] <Reading Sensor Arrangement>
[0122] The image reading units 70 and 71 are covered with sensor
cases 70a and 71a formed by mold members, respectively, and each
have a structure in which a glass is provided on the original
conveyance surface side. The image reading unit 71 is movable in
the conveyance direction and the vertical direction, and the image
reading unit 70 is fixed to the lower unit 104.
[0123] An arrangement in the sensor cases 70a and 71a of the image
reading units 70 and 71 will be described with reference to FIGS.
12A and 12B.
[0124] The sensor cases 70a and 71a include CISs 72 and 73 as
reading sensors and white reference boards 74 and 75, respectively.
Photoelectrical conversion elements placed on a line and light
emitting elements 150 and 151 for irradiating the conveyance medium
S are provided. The CIS 72 in the image reading unit 70 reads the
obverse surface of the conveyance medium S. The CIS 73 in the image
reading unit 71 reads the reverse surface of the conveyance medium
S.
[0125] The CISs 72 and 73 are identical members, and are arranged
to have point symmetry with respect to the conveyance surface. The
use of the identical members has an effect of reducing the cost,
and the arrangement is common to the obverse and reverse surfaces,
thereby implementing simplification.
[0126] The white reference boards 74 and 75 are adhered to the CISs
72 and 73, respectively. Light with which an original is irradiated
through a light guide is reflected by the white reference board 74
or 75 to enter a lens 152 or 153, and thus the background color
becomes white. A black background portion 76 or 77 is part of a
housing in which the CIS 72 or 73 and the white reference board 74
or 75 are arranged. When the CIS moves, the surface that reflects
light with which the original is irradiated via the light guide
disappears. In addition, there is a slope of an angle that prevents
reflected light from directly entering an opposite lens even if the
light reaches the black background portion. This changes the
background color into black. The inner walls of the sensor cases
70a and 71a of the image reading units 70 and 71 are made of a
material for absorbing light beams reflected by the black
background portions 76 and 77. Alternatively, members that do not
reflect light beams by absorbing them may be arranged. However, it
is preferable to provide the members to include opposite positions
in a direction parallel to the conveyance path with respect to the
black background portions 76 and 77, and set each of the slopes of
the black background portions 76 and 77 to form an angle of
45.degree. or more with respect to the conveyance path, thereby
preventing incident light from being guided in the direction of the
opposite lens by being reflected by the inner wall of the sensor
case 70a or 71a.
[0127] Referring to FIGS. 12A and 12B, the white reference board is
separated from the black background portion. However, the black
background portion may be adjacent to the white reference
board.
[0128] The white reference board 74 is adhered so that part of it
protrudes from the CIS 72 toward the light receiving/emitting
element, as shown in FIGS. 12A and 12B. Thus, the white reference
board 74 shields light traveling from the light emitting element
151 to a light receiving element 154 of the opposite sensor. That
is, the white reference board also functions as a light-shielding
plate. The white reference board 75 of the opposite sensor has the
same arrangement and has the same effect.
[0129] To improve the effect of shielding the light traveling from
the light emitting element 151 to the light receiving element 154
of the opposite CIS 72, the light emitting element 151 is
preferably adjacent to the white reference board 74 when viewed
from the conveyance path side. In other words, the light emitting
element 151 is preferably arranged so that projections of the light
emitting element 151 and the white reference board 75 onto the
conveyance path are adjacent to each other.
[0130] If the white reference board 75 and the light emitting
element 151 are close to each other, the white reference board 75
exists in a direction of the lens 152 of the opposite CIS 72 and
the light receiving element 154, thereby improving the
light-shielding effect. Therefore, the white reference board 75,
the light emitting element 151, and a light receiving element 155
are preferably arranged along the conveyance path in that order.
The same applies to the white reference board 75 of the opposite
sensor.
[0131] <Background Switching Arrangement>
[0132] A background color switching arrangement will be described
next. FIG. 11 is a plan view showing the image reading unit
according to this embodiment.
[0133] FIGS. 12A and 12B are sectional views each showing a section
Y shown in FIG. 11. FIG. 12A corresponds to a position in a white
background state and FIG. 12B corresponds to a position in a black
background state.
[0134] The CIS 72 of the image reading unit 70 transmits a driving
force of a CIS sliding motor 79 arranged in the lower unit 104 via
a transfer member 78 provided in the image reading unit 70, thereby
allowing the CIS 72 and the white reference board 74 adhered to the
CIS to move in a direction parallel to the conveyance
direction.
[0135] If the background color of a read image is set to white, the
reading position of the CIS 72 is arranged at the position of the
opposite white reference board 75, thereby enabling white
background reading. At this time, since the CIS 72 and the white
reference board 74 move integrally, if the CIS 72 is arranged at
the white background position, the white reference board 74 is
arranged at a position facing the reading position of the CIS 73,
thereby enabling white background reading.
[0136] If the background color of a read image is set to black, the
reading position of the CIS 72 is arranged at the position of the
opposite black background portion 77, thereby enabling black
background reading.
[0137] Light emitted from the light emitting element 150 in the CIS
72 is diffused on the slope of the black background portion 77 not
to enter the light receiving element 154, thereby implementing
black background reading.
[0138] If one CIS moves, the opposite sensor also relatively moves,
and it is thus possible to perform background switching by a short
distance. The movement of one CIS can switch the background colors
of the first reading sensor 70 and the second reading sensor 71 at
the same time.
[0139] If the white background reading position is set as a
reference, it is necessary to perform adjustment control of the
margin of the leading edge in accordance with the movement of the
CIS at the time of black background reading. Since the moving
amount of the CIS is determined, if the CIS 72 moves to the black
background reading position, a reading start timing is changed in
accordance with the moving amount of the CIS 72 to adjust the
margin of the leading edge.
[0140] There is provided a black reference board as a conventional
technique. Black background reading is implemented by arranging the
reading position of the CIS at the position of the black reference
board. However, if dust or paper powder adheres to the black
reference board, the black reference board is contaminated and a
reference value cannot be maintained. It is, therefore, necessary
to perform correction control. In the present invention, even if
the black background portion is contaminated, an image of the
background color is not influenced. Thus, it is possible to
maintain a black reference, and acquire a stable black reference
without need of correction and the like.
[0141] The black background portion 76, the color reference board
74, and the light receiving/emitting portion 154 are arranged from
left in the CIS 72 in FIG. 11. This arrangement can minimize the
moving distance of the CIS.
[0142] Since the black background portion 77 needs to extend over
the whole in the width direction of the apparatus, a transfer
member connecting portion 140 is preferably on the opposite side of
the black background portion.
[0143] An arrangement in which the CIS 72 moves in the conveyance
direction in the image reading unit 70 will be described with
reference to FIGS. 13, 14A, and 14B. FIG. 13 is a perspective view
showing the CIS. FIGS. 14A and 14B are sectional views each showing
the image reading unit 70 and respectively showing sections A and B
in FIG. 11.
[0144] Bosses 141 are provided in each end portion of the CIS 72
and sandwiched between the inner wall member of the image reading
unit 70 and a guide member 142. When switching the background by
driving of the CIS sliding motor 79, the CIS 72 moves along the
guide in a direction parallel to the conveyance direction. The CIS
has a feature of a short focus length, and is preferably translated
along the guide to improve the position accuracy in the vertical
direction and the conveyance direction as the reading direction. As
the material of the boss 141, a highly slidable material different
from the material of the sensor case 70a of the image reading unit
70 is preferably used.
[0145] Note that in this embodiment, the image reading units 70 and
71 are arranged in a sensor case shape to surround the CISs 72 and
73 as reading sensors, respectively. The image reading units 70 and
71 need not always be arranged in this way. An arrangement in which
a reading sensor, a reference board, and a black reference portion
or another color reference portion are movable integrally need only
be provided.
[0146] Note that in the above description of the embodiment, a
portion described concerning only the CIS 72 is preferably applied
to the CIS 73.
Second Embodiment
[0147] The second embodiment of the present invention will be
described below.
[0148] An example of a conventional image reading apparatus using a
sheet-through automatic original feeder is formed from an upper
unit and a lower unit, and the upper unit is provided with an image
reading unit for reading one surface of an original, a display unit
for a read image, various function switches for instructing to
start reading, a power switch, and the like. The upper unit is
configured to be opened/closed about a hinge opening/closing means
with respect to the lower unit at a route RT along which an
original is conveyed, thereby implementing a structure that readily
undergoes maintenance by the user, for example, cleaning of an
original conveyance path surface.
[0149] In recent years, the use purpose of the user becomes
multi-purpose, and an improvement in operability of the image
reading apparatus is required along with the multi-functionality
and automation of the apparatus reflecting the needs. To achieve
this, electronic components are provided everywhere in the
apparatus due to the high density and multi-functionality of
electrical components, thereby improving the operability. To
improve the operability, electronic components are often provided
on the front surface of an apparatus main body, which is readily
operated by the user, and are often arranged in the upper unit of
the apparatus (Japanese Patent Laid-Open No. 2015-198299).
[0150] The kinds of originals whose images are to be read by the
image reading apparatus vary, such as a general OA sheet, a very
thin sheet such as a slip, an original containing paper powder, and
a plastic card. Since dust falling from an original or
contamination in the apparatus main body is cleaned, the user has
more and more opportunities of maintaining the apparatus.
Therefore, in the image reading apparatus configured to be
opened/closed at the original conveyance path, the number of times
the upper unit is opened/closed increases.
[0151] On the other hand, to improve the operability and work
efficiency, the image reading apparatus is speeded up. As a
speed-up means, a conveyance speed at which an original is conveyed
is increased in addition to a processing speed of a CPU or the like
of the apparatus. The amount of static electricity generated at the
time of original conveyance increases along with an increase in
number of processing sheets. Occurrence of static electricity
increases the possibility that an abnormal image or an operation
error occurs due to noise or the like generated by discharge to the
image reading unit and discharge to other electronic components. To
prevent this, an anti-static brush, a ground metal plate, or the
like is provided to ground a component in the conveyance path to
steadily release charges before a certain amount of charges of
static electricity or more is accumulated.
[0152] This embodiment provides a technique of preventing static
electricity generated in the conveyance path from being accumulated
to avoid an abnormality such as an operation error of an electric
component while reducing an impact generated when closing the first
unit provided to be opened/closed and protecting electric
components and the like from damage.
[0153] In the second embodiment, the structure shown in FIGS. 1 to
10 described in the first embodiment is in common with the first
embodiment and a description thereof will be omitted. The
difference from the first embodiment will be described.
[0154] <Ground of Upper Unit>
[0155] FIG. 15 is an enlarged view showing a portion near a feeding
unit in a state in which an upper unit 103 of an image reading
apparatus A is closed with respect to a lower unit 104 according to
this embodiment.
[0156] If the upper unit 103 is made to pivot quickly when closed,
a large impact is applied when the upper unit 103 contacts the
lower unit 104, and loud noise may be generated. In the image
reading apparatus A according to this embodiment, a lock member 201
that holds the upper unit 103 in the closed state and a conductive
upper elastic member 1140 near the lock member 201 are provided. As
shown in FIG. 16, the lock member 201 includes a hook claw 203
engaged with a hook portion 202 provided in the lower unit 104, and
receives a force by a tension spring 204 in a direction (the
direction of an arrow a) in which the hook claw 203 is engaged with
the hook portion 202. When the hook portion 202 is engaged with the
hook claw 203, the upper unit 103 is maintained in the closed
state. By moving an operation arm 205 of the lock member 201 in the
direction of an arrow b, the hook claw 203 is disengaged from the
hook portion 202, thereby enabling the upper unit 103 to pivot in
an opening direction about a main body hinge 105. As the upper
elastic member 1140, for example, a wire spring such as a torsion
spring is used, and has a force enough to push up the upper unit
103 in the direction of an arrow c.
[0157] When the upper unit 103 is set in the closed state, the
upper unit 103 is closed while the upper elastic member 1140 is
elastically biased against a contact portion 1141 provided on the
side of the lower unit 104.
[0158] A slope is provided in part of the contact portion 1141.
When the upper unit 103 is in the closed state, the upper elastic
member 1140 reaches the slope to readily push up the upper unit 103
when the hook claw 203 is disengaged from the hook portion 202.
[0159] A state before the upper elastic member 1140 is biased is
indicated by dotted lines, and a state after the upper elastic
member 1140 is biased is indicated by solid lines. That is, a
distance e corresponds to the displacement amount (deflection
amount) of the upper elastic member. On the other hand, the
engagement amount of the hook portion 202 and the hook claw 203 is
represented by f. The relationship between the deflection amount
and the engagement amount is e>f. If the hook claw 203 is
disengaged from the hook portion 202, the upper unit 103 can be
pushed up by the distance e.
[0160] The end portion of the upper elastic member 1140, that is
attached to the upper unit 103, is conductive with ground of an
electric component provided in the upper unit 103, and is
conductive with ground of an electric component arranged in the
lower unit when the upper elastic member 1140 contacts the contact
portion 1141. Therefore, in the closed state of the upper unit 103,
ground can be established via the upper elastic member 1140.
[0161] As described above, a slope 1141a is provided in part of the
contact portion 1141, and the slope 1141a and the upper elastic
member 1140 are configured to contact each other immediately before
the upper unit 103 is set in the closed state. In a shape, as in
this embodiment, formed when the contact between the upper elastic
member 1140 and the contact portion 1141 contacts the contact
portion 1141 at a top portion P bent into a V-shape, the contact
can be made to contact the slope 1141a of the contact portion 1141
at a linear portion instead of contacting at the top portion P,
thereby increasing the contact area.
[0162] FIG. 17 is a front view showing the upper unit 103 of the
image reading apparatus A when viewed from the side of the
conveyance path RT according to this embodiment.
[0163] The upper elastic members 1140 are arranged outside the
original conveyance path of the original conveyance surface
together with the lock members 150, and located on the both sides
of the original conveyance path in a direction perpendicular to the
conveyance direction. With this arrangement, even if the upper unit
103 is quickly closed, the elastic members on both sides of the
upper unit 103 are uniformly deflected. It is thus possible to
prevent deformation such as instantaneous twist from occurring in
the upper unit 103 while protecting the electric components in the
upper unit 103 by reducing an impact by the upper elastic members
1140. Especially if a display screen 93 on a display panel 90, an
operation key 122 at an adjacent position, and the like are
provided in the upper unit 103, as described above, the weight of
the upper unit 103 is heavy and many components are vulnerable to
an impact, and thus it is particularly effective to reduce an
impact on the electric components.
[0164] By arranging the upper elastic members 1140 near the lock
members 150 separated from the main body hinges 105, the load at
the time of biasing less varies, thereby making it possible to
reduce an impact equally at the left and right.
[0165] FIG. 18 is a view showing the electrical connection state of
the upper elastic member 1140 in the apparatus sectional view of
the image reading apparatus A according to this embodiment.
[0166] One end of the upper elastic member 1140 contacts a
conductive upper conveyance guide 13 (for example, a metal steel
plate) provided as the conveyance path of the upper unit 103. The
upper conveyance guide 13 is electrically connected to the upper
metal member 1074 covering the image reading unit 70 (to be
described later), and is also electrically connected, via the upper
elastic member 1140, to the contact portion 1141 provided on the
side of the lower unit 104.
[0167] FIG. 19 is a front view showing the lower unit 104 of the
image reading apparatus A when viewed from the side of the
conveyance path RT according to this embodiment.
[0168] Parts of a conductive lower conveyance guide 14 (for
example, a metal steel plate) forming the conveyance path serve as
the contact portions 1141. The contact portions 1141 are located
outside the conveyable range of a conveyance medium S, and the lock
members are also located outside the conveyable range of the
conveyance medium S.
[0169] In the image reading apparatus A according to the second
embodiment of the present invention, static electricity generated
by conveyance of the conveyance medium S flows into the upper
conveyance guide 13 and the lower conveyance guide 14, and charges
flowing into the upper conveyance guide 13 are electrically
connected to the lower conveyance guide 14 by the upper elastic
members 1140. Furthermore, when the upper elastic members 1140 are
arranged on both sides of the conveyance path RT in the direction
perpendicular to the conveyance direction, and made to contact the
contact portions 1141, charges by static electricity are prevented
from moving in one direction. Therefore, it is possible to prevent
an operation error caused by noise that enters a signal of an image
reading unit 70 due to a change in electromagnetic wave generated
by the movement of the charges. Note that it is only necessary to
arrange the upper elastic member 1140 on at least one side of the
conveyance path RT, and a nonmetal elastic member may be provided
on the other side. Alternatively, no member is provided on the
other side to arrange the conveyance path RT close to the other
side, thereby implementing downsizing.
[0170] The biasing forces of the upper elastic members 1140 push up
the upper unit 103, preferably, by an amount enough to allow the
user to insert fingers into a space formed by pushing up the upper
unit 103. In this case, certain displacement amounts of the elastic
members 1140 are required, and it is accordingly necessary to
ensure certain lengths of the contact portions 1141 in a direction
parallel to a conveyance direction D1. In this embodiment, it is
possible to float the upper unit 103 to a desired height by making
the elastic members 1140 abut against portions on both sides of the
conveyance path, that have regions narrow in the width direction
and can ensure regions of certain lengths in the conveyance
direction D1. At the same time, it is possible to electrically
connect the upper unit 103 and the lower unit 104 by establishing
electrical contact. Furthermore, by establishing electrical contact
on both sides of the conveyance path, it is possible to form an
arrangement in which static electricity is readily released
electrically to both the upper unit 103 and the lower unit 104 even
if the conveyance medium S is charged by static electricity, and to
take an effective measure against static electricity and the like
in the overall arrangement instead of processing static electricity
in the lower unit 104.
[0171] As is apparent from FIG. 16, when the upper unit 103 is
closed with respect to the lower unit 102, the upper unit 103 is
closed while the upper elastic member 1140 changes the contact
position with the contact portion 1141, and the contact portion
1141 ensures a region for this.
[0172] In an arrangement in which a biasing force is simply
generated by a coil spring or the like in the tangential direction
(the direction perpendicular to the contact portion 1141) of the
pivot of the upper unit 103, if a foreign substance or a sheet
exists on the side of the contact portion 1141, it may be
sandwiched between the upper elastic member 1140 and the contact
portion 1141, and it may be difficult to reliably make the upper
elastic member 1140 contact the contact portion 1141. On the other
hand, even if a foreign substance or the like exists, the contact
portion 1141 according to this embodiment can contact the contact
portion 1141 by avoiding the foreign substance or the like when the
upper unit 103 is closed while changing the contact position with
the contact portion 1141, thereby implementing more reliable
contact.
[0173] <Ground of CIS Unit>
[0174] FIG. 20 is a view showing the electrical connection state in
the apparatus sectional view of the image reading apparatus A
according to this embodiment.
[0175] The image reading unit 70 is provided with a contact image
sensor (to be referred to as a CIS hereinafter) 71.
[0176] When inserted into a storing portion 1077a of the lower unit
104, the image reading unit 70 is inserted while biasing a metal
lower elastic member 1075 protruding from the side of the lower
unit 104, and fitted and fixed at a storage completion
position.
[0177] The lower surface of the image reading unit 70 is covered
with a lower metal member 1076, and electric components such as the
CIS 1071 in the image reading unit are protected from static
electricity. The image reading unit 70 is inserted while biasing
the lower elastic member 1075 by the lower metal member 1076, and
thus grounded with respect to the lower unit 104.
[0178] The other image reading unit 70 is arranged at a position
almost facing via the conveyance path RT, and stored, to be
movable, in a storing portion 1077b provided with the upper metal
member 1074 of the upper unit 103, and the electric components such
as the CIS 1071 are protected from static electricity. The upper
metal member 1074 has an elastic portion, and is electrically
connected to the upper conveyance guide 13 by pressing the elastic
portion against the upper conveyance guide 13. The upper metal
member 1074 may be connected using a conductive member (for
example, a torsion spring) instead of the elastic portion.
[0179] The upper metal member 1074 is electrically connected via an
anti-static brush 1079 and a metal member 1078 on the downstream
side of the upper unit 103. The anti-static brush 1079 eliminates
static electricity charged on the surface of the conveyance medium
S. The eliminated charges are electrically connected from the metal
member 1078 to the upper conveyance guide 13 via an upper metal
member 1074 to flow to ground of the lower unit 104 via the upper
elastic member 1140.
[0180] Static electricity generated on the upper portion side by
the conveyance medium S and static electricity generated on the
conveyance medium S can be electrically connected from the
anti-static brush 1079 to the side of the lower unit 104 by the
upper elastic members 1140 by electrically connecting the
respective conductive members.
[0181] Note that the upper conveyance guide 13, the upper metal
member 1074, and the metal member 1078 may be implemented by
identical components.
[0182] The upper metal member 1074 is also electrically connected
to the electric components (for example, the display screen 93, the
operation key 122, a substrate that controls detected signals of
various sensors, and the like) in the display panel 90 provided in
the upper unit 103 via conductive members 401a and 401b, and is
grounded.
[0183] <Arrangement of Lower Unit>
[0184] The lower unit 104 includes the hook portions 202 that allow
the upper unit 103 to be maintained in the closed state by engaging
with the lock members 201 provided in the upper unit 103 in order
to connect one end of the upper unit 103 by the main body hinge 105
for attaching the upper unit 103 to be rotatable and to prevent the
other end from pivoting in the opening direction by the reaction of
the upper elastic member 1140.
[0185] In addition, the lower unit 104 includes the actuator 86 for
conveying the conveyance medium S, the driving rollers 21 and 31,
the lower conveyance guide 14, the storage portion 1077 of the
image reading unit 70, the communication unit 84 for controlling
the actuator 86, a support frame 301, and the control unit 80.
[0186] One end of the lower conveyance guide 14 on the upstream
side, that is attached to the lower unit 104, is biased by a coil
spring 302, and the other end on the downstream side is connected
to the lower metal member 1076 via the lower elastic member 1075.
The side of coil spring 302, opposite to the side biasing the lower
conveyance guide 14, biases the support frame 301, thereby
electrically connecting the lower metal member 1076 and the lower
conveyance guide 14 to the support frame 301.
[0187] As described above, static electricity generated in the
lower portion side by the conveyance medium S can be electrically
connected from the lower metal member 76 to the support frame via
the respective electrical connection portions.
Third Embodiment
[0188] FIG. 21 is a schematic view showing an image reading
apparatus B according to the third embodiment. In the image reading
apparatus B, the lower elastic member 501 according to the second
embodiment is attached to the side of a lower unit 104 and a
contact portion 502 contacts part of an upper conveyance guide 13
attached to an upper unit 103. Other electrical connection routes
are the same.
[0189] As described above, each of the image reading apparatuses
according to the second and third embodiments includes a second
unit to which a first unit including an electric component is
pivotably attached, a sheet conveyance path formed between the
first unit and the second unit in a closed state in which the first
unit is closed with respect to the second unit, and an elastic
member configured to press the first unit in an opening direction
from the closed state, wherein the elastic member is a conductive
member, and in the closed state, one end of the elastic member
contacts a conductive portion of the first unit and the other end
of the elastic member contacts a conductive portion of the second
unit.
Fourth Embodiment
[0190] The fourth embodiment will be described below.
[0191] In a sheet-through reading apparatus disclosed in Japanese
Patent Laid-Open No. 2009-278383 and the like, there is a need to
detach a reading unit for the purpose of maintenance when dust
entering the reading unit in use is to be cleaned, a reading sensor
fails, or a reading glass is scratched. Normally, a facing reading
unit copes with a case in which a floated facing reading unit is
elastically pressed against a reading unit fixed to a frame to read
a thick original.
[0192] However, when detaching the reading unit, the reading unit
fixed to the frame needs to be released and pulled out of a storage
portion provided in the frame, and is thus difficult to be detached
from the frame.
[0193] This embodiment provides an image reading apparatus having
an attachment/detachment structure for facilitating cleaning and
maintenance of a reading unit placed in a conveyance path.
[0194] In the fourth embodiment, the structure shown in FIGS. 1 to
10 described in the first embodiment is in common with the first
embodiment and a description thereof will be omitted. The
difference from the first embodiment will be described.
[0195] FIGS. 24A and 24B are partial sectional views each showing
an image reading apparatus according to the fourth embodiment. An
image reading lower unit 702 includes a reading-side engaging means
7021. As shown in FIGS. 24A and 24B, when inserted into a storage
portion 1401 provided in a lower unit 104, the image reading lower
unit 702 is inserted while biasing a lower elastic member 1075
protruding from the side of the lower unit 104. In the stored
state, the image reading lower unit 702 is fitted and fixed to a
lower unit engaging portion 1042 by the reading-side engaging means
7021, as shown in FIG. 24B. If the image reading lower unit 702 is
pressed in the stored state of the image reading lower unit 702, a
butting portion 1403 provided in the lower frame storing portion
1401 regulates movement. Therefore, even if the image reading unit
702 is pressed in a state in which an upper unit 103 is opened, the
image reading lower unit 702 abuts against the butting portion 1403
without retracting from a route RT, unlike an image reading upper
unit 701, thereby regulating movement.
[0196] When the upper unit 103 is in the stored state, the image
reading upper unit 701 is pressed against the image reading lower
unit 702 by a predetermined force, and then stops if the image
reading lower unit 702 abuts against the above-described butting
portion 1403. In this state, when a conveyance medium S' thicker
than a route RT' formed between the image reading upper unit 701
and the image reading lower unit 702 enters the image reading unit
70, the image reading upper unit 701 is pushed up by the conveyance
medium S' to retract toward the upper unit 103. If the conveyance
medium S' passes through the image reading unit 70, the image
reading upper unit 701 is pressed against the image reading lower
unit 702 again by an elastic member 7011.
[0197] The embodiment of the present invention will be disclosed in
detail. Maintenance is performed in the open state of the upper
unit 103, as shown in FIG. 8. At this time, the image reading upper
unit 701 and the image reading lower unit 702 are released on the
side of the route RT.
[0198] FIGS. 23A and 23B are perspective views each showing the
image reading lower unit 702 of an image reading apparatus A
according to the fourth embodiment of the present invention. FIG.
23A shows a state in which the image reading lower unit 702 is
detached. FIG. 23B shows a state in which the image reading lower
unit 702 is stored.
[0199] Note that for the sake of simplicity, FIGS. 23A and 23B do
not illustrate the upper unit 103. The image reading lower unit 702
is regulated by adjusting the biasing force of a butting portion
1043 or the elastic member 1075 so the image reading lower unit 702
does not retract from the route RT even when pressed by the image
reading upper unit 701 facing the image reading lower unit 702 in
the stored state.
[0200] Referring to FIG. 24B, if the reading-side engaging means
7021 is deflected by inserting a tool from a hole formed on the
side of the route RT in the state in which the upper unit 103 is
opened, as shown in FIG. 8, the image reading lower unit 702 is
biased upward by the lower elastic member 1075, as shown in FIG.
24B. Thus, the image reading lower unit 702 is lifted to the route
RT by the lower elastic member 1075, and the image reading lower
unit 702 protrudes to the route RT. This structure allows the image
reading lower unit 702 to be readily detached from the image
reading apparatus A, thereby improving the maintainability.
[0201] Note that this embodiment has exemplified the structure in
which the image reading upper unit 701 and the image reading lower
unit 702 are arranged on both sides of the route RT to face each
other. The present invention, however, is not limited to this. An
arrangement in which the image reading lower unit 702 is arranged
only on one side of the route RT to read only one surface of a
conveyance medium S may be adopted. The image reading upper unit
701 and the image reading lower unit 702 may be arranged at an
interval in the conveyance direction of the route RT, instead of
arranging them to face each other.
[0202] This embodiment has explained an example in which the image
reading lower unit 702 is fixed by fitting and fixing by the lower
unit engaging portion 1042 and the reading-side engaging means
7021. The present invention, however, is not limited to this. It is
possible to obtain the same effect even if, for example, the image
reading lower unit 702 is fixed to the lower unit 104 using a
fastening member such as a screw or the image reading lower unit
702 is fixed to the lower unit 104 using a magnetic force or the
like.
[0203] Furthermore, in this embodiment, the image reading lower
unit 702 abuts against the lower frame butting portion 1403 to
regulate retraction of itself from the route RT. However, for
example, by increasing the force of the lower elastic member 1075
to be larger than that of the elastic member 7011 for pressing the
image reading upper unit 701, the image reading lower unit 702 may
be prevented from retracting when an original enters.
[0204] If, as shown in FIGS. 24A and 24B, the lower surface of the
image reading unit 702 is covered with the conductive member (lower
metal member) 1076 made of a metal such as stainless steel, the
lower surface functions as a noise shield material of an electric
component such as a CIS 1071, and the conductive member 1076 serves
as a ground surface exposed to the lower frame side of the image
reading lower unit 702.
[0205] As shown in FIG. 24B, the lower elastic member 1075 applies,
to the image reading lower unit 702, a predetermined pressure
necessary for electrical connection at the storage position of the
image reading lower unit 702. If, as shown in FIG. 24A, the lower
elastic member 1075 is made to electrically contact the lower
conveyance metal plate (contact portion) 1141, the lower elastic
member 1075 is electrically connected to the lower unit 104. In
this state, if the image reading lower unit 702 is assembled with
the lower unit 104, as shown in FIG. 13, the image reading lower
unit 702 is inserted while the conductive member 1076 is biased by
the lower elastic member 1075. Therefore, the image reading lower
unit 702 is electrically connected to the lower unit 104 at the
storage completion position, and can operate without any electrical
influence even if the charged conveyance medium S passes through
the route RT.
[0206] <Ground of Upper Unit>
[0207] FIG. 22 is a perspective view showing a state in which the
upper unit 103 of the image reading apparatus A is opened according
to the fourth embodiment.
[0208] If the upper unit 103 is made to pivot quickly to be stored,
when the upper unit 103 contacts the lower unit 104, a large impact
may be applied to generate loud noise. In the image reading
apparatus A according to this embodiment, metal upper elastic
members 1140 are provided on both sides of a separation roller 12
of the upper unit 103.
[0209] The upper unit 103 is set in the stored state while the
upper elastic members 1140 are elastically biased against contact
portions 1411 of the lower conveyance metal plates (contact
portions) 1141 provided on the side of the lower unit 104. The end
portion of each upper elastic members 1140, that is attached to the
upper unit 103, is electrically connected to ground of an electric
component provided in the upper unit 130, and is electrically
connected to ground of an electric component arranged in the lower
unit when the upper elastic member 1140 contacts the contact
portion 1411.
[0210] Therefore, in the stored state of the upper unit 103, the
upper unit 103 can be grounded by an elastic buffer member.
[0211] As described above, an image reading apparatus according to
the fourth embodiment includes a reading unit configured to read an
original conveyed along a conveyance path, an opening/closing unit
configured to be opened/closed to open the conveyance path, a
fixing means, arranged along the conveyance path, for fixing the
reading unit, and a reading unit releasing biasing means for
biasing the fixed reading unit toward a side of the conveyance
path, wherein the fixing means can be released from the side of the
conveyance path, and if fixing of the reading unit by the fixing
means is released, the reading unit is pushed out of a storage
portion to the side of the conveyance path by the reading unit
releasing biasing means.
Fifth Embodiment
[0212] The fifth embodiment will be described below.
[0213] There is known a technique of alternately switching the
background color of an original between white and black in an image
reading apparatus. If the background color is set to black, an
original size is automatically detected, an inclined original is
corrected by recognizing the boundary between the original and a
background portion by the black background, and show-through is
prevented when reading a thin original. On the other hand, by
setting the background portion to white, dust or the like adhering
to a glass surface arranged at a reading position is detected, and
a vertical stripe appearing in a read image due to dust or the like
is eliminated while white read data is used as reference data for
sensitivity correction (shading correction) of a light receiving
element.
[0214] A conventional mechanism of switching the background color
will be described with reference to FIG. 35.
[0215] A cylindrical transparent platen roller 800 and a
cylindrical background plate 801 are supported by a shaft 802 via
bearings 803. The cylindrical transparent platen roller 800 is
sealed by a cover 804 so dirt/dust does not internally adhere to
the cylindrical background plate 801. The cylindrical background
plate 801 is fixed to the shaft 802, and rotationally driven by a
motor 806 via a gear 805 fixed to the shaft 802. It is possible to
switch the background color of a read image by holding the
cylindrical background plate 801 facing the original reading
position so as to select a white portion or black portion.
[0216] However, as described in Japanese Patent Laid-Open No.
2004-320331, if a motor for switching the background color is
arranged on a side surface of the background plate, the width of
the apparatus is unwantedly increased.
[0217] This embodiment provides a technique of downsizing the image
reading apparatus.
[0218] In the fifth embodiment, the structures shown in FIGS. 1 to
10 described in the first embodiment and shown in FIG. 22 described
in the fourth embodiment are in common with the first and fourth
embodiments and a description thereof will be omitted. The
difference from the first and fourth embodiments will be
described.
[0219] <Ground of CIS Unit>
[0220] FIGS. 25A and 25B are perspective views when an image
reading lower unit 702 of an image reading apparatus A is attached
according to the fifth embodiment of the present invention. FIG.
25A shows a state before the image reading lower unit 702 is
attached. FIG. 25B shows a state after the image reading lower unit
702 is attached.
[0221] When inserted into a lower reading storing portion 1041 of a
lower unit 104, as shown in FIG. 25A, the image reading lower unit
702 is inserted while biasing metal lower elastic members 2075
protruding from the side of the lower unit 104, and fitted and
fixed at a storage completion position, as shown in FIG. 25B.
[0222] FIGS. 26A and 26B are schematic sectional views each showing
a portion around the image reading lower unit 702 of the image
reading apparatus A according to the fifth embodiment of the
present invention. FIG. 26A shows a state before the image reading
lower unit 702 is attached. FIG. 26B shows a state after the image
reading lower unit 702 is attached.
[0223] The lower surface of the image reading lower unit 702 is
covered with a metal member 2076, and grounded with an electric
component such as a CIS 2071. When inserted while biasing the lower
elastic members 2075 by the metal member 2076, the image reading
lower unit 702 is grounded with respect to the lower unit 104.
[0224] Since the image reading lower unit 702 is biased upward by
the lower elastic members 2075, it is lifted up only by releasing
fitting and fixing, and it becomes easy to detach the image reading
lower unit 702, thereby improving the maintainability.
[0225] <Arrangement of CIS>
[0226] An image reading unit according to this embodiment will be
disclosed in detail.
[0227] Each of an image reading upper unit 701 and the image
reading lower unit 702 on the downstream side of a medium detection
sensor 60 is, for example, a unit for optically scanning,
performing conversion into an electrical signal, and reading the
signal as image data, and includes a light source such as an LED,
an image sensor, and a lens array. In this embodiment, the image
reading upper unit 701 is arranged in an upper reading storage
portion (not shown) provided in an upper unit 103, and the image
reading lower unit 702 is arranged in the lower reading storing
portion 1041 provided in the lower unit 104. These reading units
read the obverse and reverse surfaces of a conveyance medium S.
However, one reading unit may be arranged in one of the upper unit
103 and the lower unit 104 to read only one surface of the
conveyance medium S. This embodiment adopts the structure in which
the image reading upper unit 701 and the image reading lower unit
702 are arranged to face each other on both sides of a route RT.
However, for example, the image reading upper unit 701 and the
image reading lower unit 702 may be arranged at an interval in the
direction of the route RT.
[0228] The image reading lower unit 702 is fixed to the lower unit
104. On the other hand, the image reading upper unit 701 is movably
supported by a press spring (not shown). This allows the image
reading upper unit 701 to be translated in a direction
perpendicular to a conveyance surface, thereby smoothly performing
image reading and conveyance of a thick original.
[0229] FIGS. 27A and 27B are vertical partial sectional views each
showing the image reading upper unit 701 and the image reading
lower unit 702 of the image reading apparatus A according to the
fifth embodiment of the present invention. FIG. 27A shows a state
when facing a white reference portion. FIG. 27B shows a state when
facing a black reference portion.
[0230] The arrangements of the image reading upper unit 701 and the
image reading lower unit 702 will be described with reference to
FIGS. 27A and 27B. The image reading upper unit 701 is formed by a
CIS 711 including a rod lens 711a for reading an image, a color
reference member 721 including a white reference portion 721a, a
contact glass 741 for guiding an original to an original reading
position, a sensor case 751 for storing the CIS 711 and the color
reference member 721 and holding the contact glass 741, and a cover
731 serving as the cover of the sensor case. In this embodiment,
the white reference portion 721a of the color reference member 721
is integrated with the CIS 711 by adhesion, bonding, coating, or
another method, and a black reference portion 721b is formed in
part of the CIS 711.
[0231] Similarly to the above arrangement of the image reading
upper unit 701, the image reading lower unit 702 is formed by a CIS
712 including a rod lens 712a for reading an image, a color
reference member 722 including a white reference portion 722a, a
contact glass 742 for guiding an original to the original reading
position, a sensor case 752 for storing the CIS 712 and the color
reference member 722 and holding the contact glass 742, and a cover
732 serving as the cover of the sensor case, and additionally
includes a translating cam 74 for moving the CIS 712 to a
predetermined position and a cam return spring 2078 for biasing the
translating cam 2074 to move the moved CIS 712 to the first
position (initial position).
[0232] FIG. 28A is a vertical partial sectional view showing the
image reading lower unit 702 when facing the black reference
portion. FIG. 28B is a horizontal partial sectional view showing
the image reading lower unit 702 when facing the black reference
portion. FIG. 29A is a vertical partial sectional view showing the
image reading lower unit 702 when facing the white reference
portion. FIG. 29B is a horizontal partial sectional view showing
the image reading lower unit 702 when facing the white reference
portion.
[0233] The CIS 712 includes the projection 712a and a projection
712b extending in the direction of an arrow z in FIG. 28A. The
projection 712a is fitted in a cam groove 2074a formed in the
translating cam 2074. Furthermore, the projection 712a is fitted,
via a sliding member 760, in an elongated hole 732a formed in the
lower cover 732, thereby regulating movement in the main scanning
direction. On the other hand, the projection 712b is fitted in a
cam groove 2074b formed in the translating cam 2074. Furthermore,
since the CIS 712 slides with the lower cover 732 via the highly
slidable sliding member 760, wear of the CIS 712 with the lower
cover 732 and cam groove 2074a by movement of the CIS 712 can be
reduced.
[0234] The translating cam 2074 includes the cam grooves 2074a and
2074b in which the projections 712a and 712b of the CIS 712 are
fitted, elongated holes 2074c and 2074d in which projections 732b
and 732c formed in the lower cover 732 are fitted, and a hook
portion 2074e on which the cam return spring 2078 is hooked.
[0235] The translating cam 2074 is locked with a locking portion
732d of the lower cover 732 by the cam return spring 2078, and
pulled in the direction of an arrow g in FIG. 28B. When facing the
white reference portion at the first position (initial position),
the projections 712a and 712b are located closer to the right side,
as shown in FIG. 28A. On the other hand, when facing the black
reference portion at a predetermined position, the projections 712a
and 712b are located closer to the left side, as shown in FIG.
29A.
[0236] In this way, when the translating cam 2074 is engaged with
the CIS 712 to be moved in the main scanning direction as the
longitudinal direction of the CIS 712, the CIS 712 is moved in a
sub-scanning direction to one of a position facing the white
reference portion 721a of the color reference member 721 provided
in the image reading upper unit 701 and a position facing the black
reference portion 721b. This switches the background color of the
original when reading an image of the original.
[0237] If only the CIS 712 is moved as in this embodiment, a load
on a CIS sliding motor 2073 can be decreased, thereby downsizing
the motor and reducing the power consumption.
[0238] Note that it is possible to determine, based on an output
from a position detection sensor 770, whether the CIS 712 has been
moved to the position facing the white reference portion 721a of
the color reference member 721 or the position facing the black
reference portion 721b. The position detection sensor 770 is a
detection means for detecting the position of the translating cam
2074, and indirectly detects which of the white reference portion
721a and the black reference portion 721b the position of the CIS
712 faces, by detecting the position of the translating cam
2074.
[0239] In this image reading apparatus, when the CIS 712 moves
between the position facing the white reference portion 721a and
the position facing the black reference portion 721b, if the CIS
712 shifts with respect to the original image reading position, the
edge position in original reading (the reading position) unwantedly
shifts. If the edge position shifts, an image at the leading edge
or trailing edge of the original is missed, thereby degrading the
quality of the read image. To prevent the edge position from
shifting, the position of the CIS 712 at the time of original
reading is detected using the position detection sensor 770.
[0240] In this embodiment, the edge position is prevented from
shifting by changing, between the position facing the white
reference portion and the position facing the black reference
portion, a timing after the medium detection sensor 60 detects the
leading edge of the original before reading of an image of the
original starts in accordance with the position of the CIS 712
detected by the position detection sensor 770.
[0241] In this embodiment, the position detection sensor 770 is
arranged on the opposite surface of the conveyance surface of the
image reading lower unit 702 of the lower reading storing portion
1041 provided in the lower unit 104, as shown in FIG. 30.
[0242] The operation of detecting the position of the translating
cam 2074 by the position detection sensor 770 will be described
with reference to FIG. 31.
[0243] When the power of the image reading apparatus is turned on,
the translating cam 2074 is moved in the direction of an arrow a in
FIG. 31 to a position where a projecting portion 2074g of the
translating cam 2074 blocks a slit 770a of the position detection
sensor 770 shown in FIG. 17 (a position where the position
detection sensor 770 is turned on: BP). The position BP is a
position where the CIS 712 faces the black reference portion 712b.
Then, the translating cam 2074 is moved in the direction of an
arrow b in FIG. 31 to a position (WP) where a gear 2079 (to be
described later) is half rotated. The position WP is a position
where the CIS 712 faces the white reference portion 712a. This
series of operations is the initialization operation of the
background switching mechanism that is performed every time the
power of the apparatus is turned on.
[0244] After the initialization operation, if the background color
is set to white to start image reading, white reference data for
shading correction is read by maintaining the translating cam 2074
at the position WP without moving it. An image of a conveyed
original is then read.
[0245] If the background color is set to black, after white
reference data for shading correction is read, similarly to the
case in which the background color is white, the translating cam
2074 is moved to the position BP to read an image of a conveyed
original.
[0246] The arrangement of a CIS driving unit will be described next
with reference to FIGS. 32 and 33.
[0247] FIG. 32 is a perspective view showing a portion around the
CIS driving unit in a state in which the image reading lower unit
702 is detached. FIG. 33 is a partial sectional view showing the
portion around the CIS driving unit.
[0248] As shown in FIG. 32, the lower unit 104 includes a through
hole 104a through which a fitting portion of the CIS sliding motor
2073 and the translating cam 2074 extends.
[0249] Furthermore, a protruding portion 104c is provided in the
lower reading storing portion 1041 of the lower unit 104 to cover
the through hole 104a and the CIS driving unit (to be described
later). The protruding portion 104c reduces accumulation of a paper
powder falling from the conveyance path to the lower reading
storing portion 1041 through the through hole 104a on a component
provided in the lower unit 104 or the CIS driving unit.
[0250] As shown in FIG. 33, the CIS driving unit includes the gear
2079 that transfers a driving force to the translating cam 2074,
the CIS sliding motor 2073 that operates a pinion gear 2077, and
the pinion gear 2077 that is pressed in the CIS sliding motor 2073
and abuts against the gear 2079.
[0251] A projection 2079a fitted in a cam groove 2074f formed in
the translating cam 2074 is provided in the gear 2079. If the CIS
sliding motor 2073 rotates, a driving force is transferred to the
pinion gear 2077, the gear 2079, and the translating cam 2074, and
the translating cam 2074 moves in the main scanning direction.
[0252] As shown in FIG. 34, the CIS sliding motor 2073 is arranged
on the surface opposite to the conveyance path of the lower reading
storing portion 1041 provided in the lower unit 104. That is, the
CIS sliding motor 2073 is arranged on the surface of the image
reading lower unit 702 opposite to the surface on the conveyance
path side via the lower reading storing portion 1041. It is
possible to decrease the dimension in the width direction of the
apparatus main body by arranging the CIS sliding motor 2073 on the
surface of the image reading lower unit 702 opposite to the surface
on the conveyance path side.
[0253] By integrating the CISs 711 and 712 and the color reference
members 721 and 722, respectively, as in this embodiment, it is
possible to switch the background colors of the obverse and reverse
surfaces only by moving one CIS 712 even in the image reading
apparatus for double-sided simultaneous reading. Therefore, it is
unnecessary to provide, for each of the two reading units 701 and
702, the translating cam 2074 and the CIS driving unit for driving
the unit. As a result, it is possible to downsize the apparatus by
reducing the space where these components are provided, and reduce
the cost of the apparatus by decreasing the number of
components.
[0254] In this embodiment, the CIS driving unit is arranged not in
the reading lower unit 702 but in the lower unit 104, thereby
making it possible to detach only the reading lower unit 702 from
the apparatus. The unit dealt with in maintenance is small, thereby
improving the maintainability.
[0255] Especially, by providing the translating cam 2074 for moving
the CIS 712 under the image reading lower unit 702, it is possible
to switch the background without widening the image reading
apparatus A in the width direction.
[0256] As described above, the image reading apparatus according to
the fifth embodiment includes an apparatus main body including a
conveyance means for conveying an original, a sensor case mounted
along a conveyance path of the apparatus main body, a reading
sensor provided to be movable in a conveyance direction of the
original in the sensor case and configured to read one surface of
the original, a background member provided to face the reading
sensor via the conveyance path and including a first background
portion and a second background portion arranged side by side in
the conveyance direction of the original, and a sensor moving
member configured to move the reading sensor in the conveyance
direction of the original, wherein the sensor moving member is
engaged with the reading sensor by being attached to the sensor
case from an opposite side of the conveyance path, and includes a
driving source configured to transfer a driving force from an
opposite side of the side of the reading sensor to the sensor
moving member.
[0257] The present invention is not limited to the above-described
embodiments, and various changes and modifications can be made
within the spirit and scope of the present invention. Therefore, to
apprise the public of the scope of the present invention, the
following claims are made.
* * * * *